The present invention relates to an automotive compressor and in particular to a snap-on cover that is easily installed onto the compressor clutch pulley to prevent circulation of dust through the compressor clutch assembly, thereby increasing the service life of the clutch assembly.
More particularly, the present invention is applicable to a compressor clutch assembly in which a pulley is continuously driven and torque is selectively transmitted to the compressor crankshaft by a clutch mechanism. In such an arrangement, the clutch assembly is located adjacent to the pulley on the side of the pulley opposite the compressor housing. Exposure of the clutch mechanism to a harsh operating environment, i.e., in an agricultural application, causes premature failure of clutch components, particularly the clutch pulley bearings.
A metal cover attached with screws to the front surface of the pulley has been used to limit the flow of air through the compressor clutch assembly. A flexible segmented clutch enclosure for attaching with screws to a stationary bell housing has been used in automotive transmission applications to prevent entry of foreign material into the clutch parts. In U.S. Pat. No. 1,089,972, a safety shield for a friction clutch mechanism is disclosed wherein a hollow guard member is secured to the pulley by screws or bolts inward with respect to the pulley rim.
In each of the aforementioned clutch covers, a problem arises in that additional pulley size and material is required of providing holes to attach the cover to the pulley b means of screws or bolts. This increases the weight and space requirements for the compressor assembly and there is a possibility of the screws loosening as a result of engine vibration. Furthermore, increased difficulty and, thus, higher manufacturing costs are associated with installing and removing bolt-on covers.